Surgical instrument with stopper assembly

ABSTRACT

A surgical instrument includes a housing, an elongated member that extends distally from the housing and defines a longitudinal axis, an end effector assembly coupled to a distal portion of the elongated member, and a stopper assembly operably coupled to the proximal portion of the outer shaft member. The stopper assembly is disposed within one or more cavities defined within the housing. The stopper assembly is configured to prevent longitudinal movement of the outer shaft member along the longitudinal axis and to rotate within the one or more cavities upon rotation of the elongated member about the longitudinal axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 14/574,693 filed on Dec. 18, 2014, the entire contents of which are incorporated herein by reference.

INTRODUCTION

The present disclosure relates generally to the field of surgical instruments. In particular, the disclosure relates to an endoscopic electrosurgical forceps having a housing including a mechanism disposed therein that prevents longitudinal movement of an elongated member extending from the housing.

BACKGROUND

Electrosurgical forceps are commonly used in open and endoscopic surgical procedures to coagulate, cauterize and seal tissue. Such forceps typically include a housing and a pair of jaws disposed on a distal portion of an elongated member extending from the housing. The pair of jaws can be controlled by a surgeon to grasp targeted tissue, such as, e.g., a blood vessel. The jaws may be approximated to apply a mechanical clamping force to the tissue, and are associated with at least one electrode to permit the delivery of electrosurgical energy to the tissue. The combination of the mechanical clamping force and the electrosurgical energy has been demonstrated to join adjacent layers of tissue captured between the jaws. When the adjacent layers of tissue include the walls of a blood vessel, sealing the tissue may result in hemostasis, which may facilitate the transection of the sealed tissue. A detailed discussion of the use of an electrosurgical forceps may be found in U.S. Pat. No. 7,255,697 to Dycus et al.

Operation of the electrosurgical forceps typically involves longitudinal actuation of the internal components of the elongated member as well as rotational actuation of the elongated member. During use, longitudinal actuation of such internal components may result in inadvertent longitudinal movement of the elongated member relative to the housing. Thus, the elongated member must be prevented from longitudinal movement while its rotational actuation functionality is maintained.

SUMMARY

The present disclosure relates to a surgical instrument that includes a housing, an elongated member that extends distally from the housing and defines a longitudinal axis, an end effector assembly coupled to a distal portion of the elongated member, and a stopper assembly operably coupled to the proximal portion of the outer shaft member. The elongated member is configured to rotate about the longitudinal axis and includes an outer shaft member having a proximal portion disposed within the housing. The end effector assembly includes a pair of opposing jaw members moveable relative to each other to grasp tissue therebetween. At least one of the jaw members is adapted to connect to an electrosurgical energy source for conducting electrosurgical energy through grasped tissue. The stopper assembly is disposed within at least one cavity defined within the housing. The stopper assembly is configured to prevent longitudinal movement of the outer shaft member along the longitudinal axis and to rotate within the at least one cavity upon rotation of the elongated member about the longitudinal axis.

Additionally or alternatively, the stopper assembly includes at least one annular member coupled to an outer surface of the outer shaft member and includes at least one slot defined through the annular member perpendicular to the longitudinal axis.

Additionally or alternatively, the outer shaft member defines at least one groove therein perpendicular to the longitudinal axis, the at least one groove configured to align with the at least one slot of the at least one annular member.

Additionally or alternatively, the at least one groove of the outer shaft member and the at least one slot of the annular member are configured to receive a clip therein to couple the at least one annular member to the outer shaft member.

Additionally or alternatively, the diameter of the outer shaft member is less than a diameter of the at least one annular member.

Additionally or alternatively, the at least one cavity is defined by a distal wall and a proximal wall each defining an annular clearance configured to receive the outer shaft member therethrough.

Additionally or alternatively, the diameter of the at least one annular member is greater than a diameter of the annular clearance of at least one of the distal wall or the proximal wall such that the at least one annular member engages at least one of the distal wall or the proximal wall.

Additionally or alternatively, at least one annular member includes an inner surface defining at least one rib configured to engage a longitudinal slot defined through the proximal portion of the outer shaft member.

Additionally or alternatively, the stopper assembly includes a first annular member and a second annular member, the first annular member restricting proximal longitudinal movement of the outer shaft member along the longitudinal axis and the second annular member restricting distal longitudinal movement of the outer shaft member along the longitudinal axis.

Additionally or alternatively, the stopper assembly includes at least one surface structure protruding from an outer surface of the outer shaft member, the at least one surface structure configured to engage at least one wall defining the at least one cavity.

Additionally or alternatively, the stopper assembly includes a key member disposed within a key slot extending through the proximal portion of the outer shaft member, at least a portion of the key member protruding from the outer shaft member and configured to engage at least one wall defining the at least one cavity.

In another aspect, the present disclosure relates to a surgical instrument that includes a housing having at least one cavity defined therein, an elongated member that extends distally from the housing and defines a longitudinal axis, an end effector assembly coupled to a distal portion of the elongated member, and a stopper assembly operably coupled to the proximal portion of the outer shaft member. The elongated member is configured to rotate about the longitudinal axis and includes an outer shaft member having a proximal portion disposed within the at least one cavity. The end effector assembly includes a pair of opposing jaw members moveable relative to each other to grasp tissue therebetween. At least one of the jaw members is adapted to connect to an electrosurgical energy source for conducting electrosurgical energy through grasped tissue. The stopper assembly is rotatable within the at least one cavity upon rotation of the elongated member and about the longitudinal axis. The stopper assembly is configured to engage at least one wall defining the at least one cavity to prevent longitudinal movement of the outer shaft member along the longitudinal axis.

Additionally or alternatively, the stopper assembly includes at least one lance protruding from the outer shaft member.

In another aspect, the present disclosure relates to a surgical instrument that includes a housing at least one cavity defined therein, an elongated member that extends distally from the housing and defines a longitudinal axis, an end effector assembly coupled to a distal portion of the elongated member, and a stopper assembly operably coupled to the proximal portion of the outer shaft member. The at least one cavity in the housing is defined by a distal wall and a proximal wall each defining an annular clearance. The elongated member is configured to rotate about the longitudinal axis and includes an outer shaft member having a proximal portion disposed within the annular clearance of the distal and proximal walls. The end effector assembly includes a pair of opposing jaw members moveable relative to each other to grasp tissue therebetween. At least one of the jaw members is adapted to connect to an electrosurgical energy source for conducting electrosurgical energy through grasped tissue. The stopper assembly is rotatable within the at least one cavity upon rotation of the elongated member about the longitudinal axis. The stopper assembly includes a diameter that is greater than a diameter of at least one of the annular clearances defined by one of the distal wall or the proximal wall such that the stopper assembly is configured to engage at least one of the distal wall or the proximal wall to prevent longitudinal movement of the outer shaft member along the longitudinal axis.

Additionally or alternatively, the stopper assembly is configured to be welded to the outer shaft member.

Additionally or alternatively, the stopper assembly includes at least one surface structure protruding from an outer surface of the outer shaft member and configured to engage the distal wall to prevent longitudinal movement of the outer shaft member along the longitudinal axis.

According to another aspect of the present disclosure, the stopper assembly includes a key member disposed within a key slot extending through the proximal portion of the outer shaft member, at least a portion of the key member protruding from the outer shaft member and configured to engage the distal wall to prevent longitudinal movement of the outer shaft member along the longitudinal axis.

Additionally or alternatively, a diameter of the outer shaft member is less than a diameter of the at least one annular member.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the detailed description of the embodiments given below, serve to explain the principles of the disclosure.

FIG. 1A is a perspective view of an electrosurgical forceps according to an embodiment of the present disclosure including a housing, an elongated member, and an end effector assembly;

FIG. 1B is an enlarged perspective view of the end effector assembly of FIG. 1A;

FIG. 2 is a partial, side view of a proximal portion of the electrosurgical forceps of FIG. 1 including a housing having a stopper assembly disposed therein;

FIG. 3A is an enlarged side view of an embodiment of the stopper assembly of FIG. 2 including an annular member coupled to an outer shaft member of the elongated member;

FIG. 3B is an enlarged perspective view of the annular member of FIG. 3A;

FIG. 4A is an enlarged side view of an embodiment of the stopper assembly of FIG. 2 including an annular member clipped to the outer shaft member;

FIG. 4B is a perspective view of the outer shaft member and the stopper assembly of FIG. 4A with parts separated;

FIG. 5A is an enlarged side view of an embodiment of the stopper assembly of FIG. 2 including two annular members removably fixed to the outer shaft member;

FIG. 5B is a perspective view of the outer shaft member and the stopper assembly of FIG. 5A with parts separated;

FIG. 6A is an enlarged side view of an embodiment of the stopper assembly of FIG. 2 including surface structures disposed on an outer surface of the outer shaft member;

FIG. 6B is a perspective view of a portion of the outer shaft member of FIG. 6A showing the surface structures disposed on the outer surface thereof;

FIG. 6C is a cross-sectional view of the outer shaft member of FIG. 6B taken along section line 6C-6C of FIG. 6B;

FIG. 7A is an enlarged side view of an embodiment of the stopper assembly of FIG. 2 including a key member inserted into a key slot defined through the outer shaft member;

FIG. 7B is a perspective view of the outer shaft member of FIG. 7A with the key member separated from the key slot; and

FIG. 7C is a perspective view of a portion of the outer shaft member of FIG. 7A showing the key member inserted into the key slot.

DETAILED DESCRIPTION

Embodiments of the presently disclosed surgical system, instruments, and methods will now be described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein, the term “distal” refers to that portion of the surgical instrument or components thereof, farther from the user, while the term “proximal” refers to that portion of the surgical or components thereof, closer to the user.

The present disclosure generally provides for a surgical instrument having an end effector assembly, an elongated member defining a longitudinal axis, and a housing. The elongated member includes an outer shaft member having a proximal portion secured within the housing. A stopper assembly is disposed on the proximal portion of the outer shaft member and prevents longitudinal movement of the outer shaft member with respect to the housing while allowing the elongated member, including the outer shaft member, to freely rotate about the longitudinal axis defined by the elongated member.

In some embodiments, the stopper assembly includes one or more annular members fixed to the outer shaft member and disposed within a cavity defined within the housing. In some embodiments, the stopper assembly includes surface structures (e.g., protrusions, recesses, grooves, slots) formed on the outer shaft member using a machining process.

In some embodiments, the stopper assembly includes a key member disposed within a key slot defined through the outer shaft member such that the key member is disposed within a cavity defined within the housing.

Referring initially to FIGS. 1 and 2, an embodiment of an electrosurgical forceps 10 generally includes a housing 12 coupled to a proximal portion 16 b of an elongated member 16. The housing 12 supports various actuators for remotely controlling an end effector assembly 14 coupled to a distal portion 16 a of the elongated member 16. The end effector assembly 14 includes a pair of opposing jaw members 30, 32 mechanically coupled to the elongated member 16 about a pivot 44. Although this configuration is typically associated with instruments for use in laparoscopic or endoscopic surgical procedures, various aspects of the present disclosure may be practiced with traditional open instruments and in connection with endoluminal procedures as well.

The housing 12 is constructed of a right housing half 12 a and a left housing half 12 b. The left and right designation of the housing halves 12 a, 12 b refer to the respective directions as perceived by an operator using the forceps 10. The housing halves 12 a, 12 b may be constructed of sturdy plastic, and may be joined to one another by adhesives, ultrasonic welding or other suitable assembly methods.

To mechanically control the end effector assembly 14, the housing 12 supports a stationary handle 20, a movable handle 22, and a rotation knob 28. The movable handle 22 is movable relative to the stationary handle 20 to move the end effector assembly 14 between an open configuration (FIGS. 1A and 1B) wherein the jaw members 30, 32 are disposed in spaced relation relative to one another, and a closed configuration (not shown) wherein the jaw members 30, 32 are approximated.

A trigger 26 is supported by the housing 12 and is operable to extend and retract a knife 70 (FIGS. 1A and 1B) through the end effector assembly 14 when the end effector assembly 14 is in the closed configuration. The rotation knob 28 serves to rotate the elongated member 16 and the end effector assembly 14 about a longitudinal axis “A-A” defined by the elongated member 16.

To electrically control the end effector assembly 14, the housing 12 supports a switch 36 thereon, which is operable by the user to initiate and terminate the delivery of electrosurgical energy to the end effector assembly 14. The switch 36 is in electrical communication with an electrosurgical energy source, such as, for example, a generator 40 (see FIG. 1) or a battery (not shown) supported within the housing 12. The generator 40 may include devices such as the LIGASURE® Vessel Sealing Generator and the Force Triad® Generator as sold by Covidien LP. A cable 42 extends from the housing 12 to the generator 40 to electrically couple the end effector assembly 14 to the generator 40. More specifically, the jaw members 30, 32 are electrically coupled to the generator 40 (e.g., via suitable wiring extending through the elongated member 16 and the housing 12) to provide an electrical pathway to a pair of electrically conductive, tissue sealing surfaces 48, 50 disposed on the jaw members 30, 32, respectively. Sealing surfaces 48 and 50 may be electrically coupled to terminals of opposite polarity, e.g., positive (+) and negative (−), associated with the generator 40 to deliver bipolar energy to tissue grasped between jaw members 30, 32. Alternatively, the sealing surfaces 48 and 50 may be configured to deliver monopolar energy to tissue. In a monopolar configuration, one or both sealing plates 48 and 50 deliver electrosurgical energy from a positive (+) terminal and a return pad (not shown) is placed on a patient to provide a return path to the negative (−) terminal.

Electrosurgical energy may be delivered to tissue clasped between the jaw members 30, 32 through the sealing surfaces 48, 50 to effect a tissue seal. Once a tissue seal is established, the knife 70 may be advanced distally to transect the sealed tissue. The knife 70 is depicted in FIGS. 1A and 1B as extending from the elongated member 16 while the end effector assembly 14 is in an open configuration. In some embodiments, a mechanism (not shown) may be provided to prevent advancement of the knife 70 through the jaw members 30, 32 when the end effector assembly 14 is in the open configuration.

The elongated member 16 includes various longitudinal components that operatively couple the end effector assembly 14 to the various actuators supported by the housing 12. Referring now to FIG. 2, an outer shaft member 60 defines an exterior surface of the elongated member 16 and supports movement of other components therethrough as described below. A spindle 90 is disposed within the housing 12 and serves to secure at least a portion of the outer shaft member 60 within the housing 12. The spindle 90 includes an annular throughbore (not shown) defined therethrough, through which the proximal portion 60 b of the outer shaft member 60 extends, thereby ensuring proper alignment of the elongated member 16 relative to the housing 12. In some embodiments, the outer shaft member 60 may rotate about the longitudinal axis “A-A” relative to the spindle 90. In other embodiments, outer shaft member 60 may be fixedly coupled to spindle 90 such that rotation of outer shaft member 60 about the longitudinal axis “A-A” translates corresponding rotation of spindle 90. A spring 19 is disposed about the outer shaft member 60 within housing 12 and is caused to compress against a proximal surface 90 b of spindle 90 when trigger 26 is actuated (not shown) to induce advancement of the knife 70 along the longitudinal axis “A-A” and through the jaw members 30, 32. Specifics of the operation of the trigger 26 to induce advancement of the knife 70 through the jaw members 30, 32 is described in U.S. Patent Application Publication No. 20130296922, the entire contents of which is incorporated herein by reference.

A stopper assembly 62 coupled to the proximal portion 60 b of the outer shaft member 60 is disposed within a cavity 13 defined within housing 12 between a distal interior wall 21 a and a proximal interior wall 21 b (see, e.g., FIG. 3A). As described below with reference to the various embodiments shown in FIGS. 3A-7C, the stopper assembly 62 serves to prevent longitudinal movement of the outer shaft member 60 along the longitudinal axis “A-A”.

Referring now to FIGS. 3A and 3B, one embodiment of a stopper assembly 162 is shown and includes an annular member 164 disposed on the proximal portion 60 b of the outer shaft member 60. Annular member 164 includes a diameter “D2” that is larger than a diameter “D1” of the outer shaft member 60. An inner surface 164 a of the annular member 164 defines a through hole 166 configured to receive outer shaft member 60 therethrough such that an outer surface 61 of outer shaft member 60 engages the inner surface 164 a of annular member 164. Annular member 164 may be fixed to outer shaft member 60 using various suitable methods such as, for example, friction fit, adhesives, and welding. Annular member 164 defines a pair of opposing slots 168 a, 168 b therethrough perpendicular to longitudinal axis “A-A” and extending between outer surface 164 b and inner surface 164 a to define a pair of corresponding inner surfaces 167 a, 167 b. Welding materials or adhesive may be applied to the inner surfaces 167 a, 167 b to couple annular member 164 to the outer surface 61 of the outer shaft member 60. While annular member 164 is shown in FIG. 3B to include a pair of slots 168 a, 168 b, in some embodiments annular member 164 may include a single slot or, alternatively, three or more slots. In some embodiments, annular member 164 may be welded to outer shaft member 60 through slots 168 a, 168 b, via welding, laser welding, or any other suitable welding method. An advantage of welding the annular member 164 to outer shaft member 60 through the slots 168 a, 168 b is that welding materials used in the welding process (e.g., metal, thermoplastic, etc.) remain within slots 168 a, 168 b instead of on the outer surface 164 b of annular member 164 or around the outer perimeter of the annular member 164.

Annular member 164 is free to rotate within cavity 13 upon rotation of elongated member 16 about longitudinal axis “A-A” and is prevented from distal longitudinal movement by engagement with distal wall 21 a and proximal longitudinal movement by a distal surface 90 a of spindle 90. Spindle 90, in turn, is prevented from proximal longitudinal movement by engagement of distal surface 90 a with proximal wall 21 b. Distal wall 21 a defines an annular clearance “C” through which outer shaft member 60 longitudinally extends. Since annular member 164 is fixedly coupled to outer shaft member 60 and the diameter “D2” of annular member 164 is greater than the diameter of annular clearance “C”, distal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented. Due to the engagement of annular member 164 with the distal surface 90 a of spindle 90, proximal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented.

Referring now to FIGS. 4A and 4B, another embodiment of a stopper assembly 262 is shown and includes an annular member 264 disposed around the proximal portion 60 b of the outer shaft member 60. Annular member 264 defines a pair of opposing slots 268 a, 268 b therethrough perpendicular to longitudinal axis “A-A” and extending between an outer surface 264 b and an inner surface 264 a of annular member 264. Slots 268 a, 268 b are configured to receive free-ends 202 a, 202 b of a generally U-shaped clip member 200. In this embodiment, the proximal portion 60 b of outer shaft member 60 includes a pair of opposing grooves 64 a, 64 b formed circumferentially within a portion of outer surface 61. Outer shaft member 60 is disposed through annular member 264 such that slots 268 a, 268 b of annular member 264 are disposed in general alignment with grooves 64 a, 64 b of outer shaft member 60. Thus, free-ends 202 a, 202 b may be received within slots 268 a, 268 b and grooves 64 a, 64 b. Free-ends 202 a, 202 b are biased inwardly toward each other to aid in maintaining the clip member 200 within slots 268 a, 268 b and grooves 64 a, 64 b.

As substantially described above with respect to annular member 164 shown in FIGS. 3A and 3B, annular member 264 is disposed within and is free to rotate within cavity 13 upon rotation of elongated member 16 about longitudinal axis “A-A”. Since annular member 264 is coupled to outer shaft member 60 and a diameter “D3” of annular member 264 is greater than the diameter of annular clearance “C”, distal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented. Due to the engagement of annular member 264 with the distal surface 90 a of spindle 90, proximal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented.

Referring now to FIGS. 5A and 5B, another embodiment of a stopper assembly 362 is shown and includes a distal annular member 364 disposed within cavity 13 and a proximal annular member 374 disposed within a cavity 15 defined within housing 12 proximal to cavity 13. Proximal and distal annular members 364, 374 each include a diameter “D4” that is larger than the diameter “D1” of outer shaft member 60. Distal annular member 364 prevents distal and proximal longitudinal movement of outer shaft member 60 and proximal annular member 374 prevents distal longitudinal movement of outer shaft member 60. Distal annular member 364 includes an inner surface 364 a defining two pairs of opposing ribs 365 a, 365 b configured to engage a distal portion of longitudinal slots 63 a, 63 b, respectively, in a friction-fit manner. Likewise, proximal annular member 374 includes an inner surface 374 a defining two pairs of opposing ribs 375 a, 375 b configured to engage a proximal portion of slots 63 a, 63 b, respectively, in a friction-fit manner.

With reference to FIG. 5B, each of longitudinal slots 63 a, 63 b include a widened middle portion (only viewable with respect to longitudinal slot 63 a) to aid in coupling and decoupling of distal and proximal annular members 364, 374 with outer shaft member 60. Specifically, distal and proximal annular members 364, 374 may be coupled to outer shaft member 60 by inserting the pairs of ribs 365 a, 365 and 374 a, 374 b into corresponding longitudinal slots 63 a, 63 b at the widened middle portion. Distal annular member 364 may then be translated distally such that the pairs of ribs 365 a, 365 b friction-fit into the distal portion of the respective longitudinal slots 63 a, 63 b. Similarly, proximal annular member 374 may then be translated proximally such that the pairs of ribs 375 a, 375 b friction-fit into the proximal portion of the respective longitudinal slots 63 a, 63 b.

As substantially described above with respect to annular member 164 shown in FIGS. 3A and 3B, distal annular member 364 is disposed within and is free to rotate within cavity 13 upon rotation of elongated member 16 about longitudinal axis “A-A”. As referring to FIG. 5A, since distal annular member 364 is coupled to outer shaft member 60 and diameter “D4” of distal annular member 364 is greater than the annular clearance “C”, distal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented. Due to the engagement of distal annular member 364 with the distal surface 90 a of spindle 90, proximal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented. Distal longitudinal movement of outer shaft member 60 is also prevented due to the engagement of proximal annular member 374 with proximal surface 90 b of spindle 90.

Referring now to FIGS. 6A-6C, another embodiment of a stopper assembly 462 having a protruded portion 450 that includes a plurality of lances, for example lances 464 a, 464 b, and 464 c, extending from the outer surface 61 of the proximal portion 60 b of outer shaft member 60. In constructing outer shaft member 60 to include lances (e.g., lances 464 a, 464 b, 464 c) as shown in FIGS. 6A-6C, stamping, punching, or other suitable processes may be employed to initially generate a flat blank of material (e.g., sheet metal) that includes a suitable profile. Thereafter, openings may be formed through the flat blank of material by any suitable equipment (e.g., metal-working equipment) and the flat blank of material pulled by a tool at the openings or pushed outward by a suitable expansion tool at the openings to create outward extending lances.

As shown in FIG. 6C, lances 464 a-c effectively increase the diameter “D1” of outer shaft member 60 at the protruded portion 450 to diameter “D5”. The protruded portion 450 of outer shaft member 60 is disposed within and is free to rotate within cavity 13 upon rotation of elongated member 16 about longitudinal axis “A-A”. Since the diameter of the annular clearance “C” is less than the diameter “D5” of protruded portion 450, outer shaft member 60 is prevented from distal longitudinal movement along longitudinal axis “A-A” by engagement of the protruded portion 450 with distal wall 21 a. Outer shaft member 60 is prevented from proximal longitudinal movement along longitudinal axis “A-A” by engagement with distal surface 90 a of spindle 90. Spindle 90, in turn, is prevented from proximal longitudinal translation along longitudinal axis “A-A” by proximal wall 21 b.

Referring now to FIGS. 7A-C, another embodiment of a stopper assembly 562 is shown and includes a key slot 66 extending through outer shaft member 60 and configured to receive a key member 564 therein in a friction fit manner. Key member 564 includes a length “L1” that is greater than the diameter “D1” of outer shaft member 60. As such, when key member 564 is inserted into key slot 66, as shown in FIG. 7C, end portions 564 a, 564 b of key member 564 protrude from opposite sides of outer shaft member 60. Referring to FIG. 7A, key member 564 is disposed within and free to rotate within cavity 13 upon rotation of elongated member 16 about longitudinal axis “A-A.” Since key member 564 is fixedly coupled to outer shaft member 60 and the length “L1” is greater than the diameter of the annular clearance “C,” distal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented due to engagement of the protruding end portions 564 a, 564 b of key member 564 with distal wall 21 a. Similarly, due to engagement of the end portions 564 a, 564 b of key member 564 with the distal surface 90 a of spindle 90, proximal longitudinal movement of outer shaft member 60 along longitudinal axis “A-A” is prevented. Spindle 90, in turn, is prevented from proximal longitudinal movement along longitudinal axis “A-A” by proximal wall 21 b. As would be understood by those of skill in the art, internal components of elongated member 16 (e.g., knife 70) may be configured with a suitable feature (e.g., slot, recess, aperture) to accommodate key member 564 therethrough such that key member 564 does not impede longitudinal motion of these internal components along longitudinal axis “A-A”.

While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as examples of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

The various embodiments disclosed herein may also be configured to work with robotic surgical systems and what is commonly referred to as “Telesurgery.” Such systems employ various robotic elements to assist the surgeon in the operating room and allow remote operation (or partial remote operation) of surgical instrumentation. Various robotic arms, gears, cams, pulleys, electric and mechanical motors, etc. may be employed for this purpose and may be designed with a robotic surgical system to assist the surgeon during the course of an operation or treatment. Such robotic systems may include remotely steerable systems, automatically flexible surgical systems, remotely flexible surgical systems, remotely articulating surgical systems, wireless surgical systems, modular or selectively configurable remotely operated surgical systems, etc.

The robotic surgical systems may be employed with one or more consoles that are next to the operating theater or located in a remote location. In this instance, one team of surgeons or nurses may prep the patient for surgery and configure the robotic surgical system with one or more of the instruments disclosed herein while another surgeon (or group of surgeons) remotely control the instruments via the robotic surgical system. As can be appreciated, a highly skilled surgeon may perform multiple operations in multiple locations without leaving his/her remote console which can be both economically advantageous and a benefit to the patient or a series of patients.

The robotic arms of the surgical system are typically coupled to a pair of master handles by a controller. The handles can be moved by the surgeon to produce a corresponding movement of the working ends of any type of surgical instrument (e.g., end effectors, graspers, knifes, scissors, etc.) which may complement the use of one or more of the embodiments described herein. The movement of the master handles may be scaled so that the working ends have a corresponding movement that is different, smaller or larger, than the movement performed by the operating hands of the surgeon. The scale factor or gearing ratio may be adjustable so that the operator can control the resolution of the working ends of the surgical instrument(s).

The master handles may include various sensors to provide feedback to the surgeon relating to various tissue parameters or conditions, e.g., tissue resistance due to manipulation, cutting or otherwise treating, pressure by the instrument onto the tissue, tissue temperature, tissue impedance, etc. As can be appreciated, such sensors provide the surgeon with enhanced tactile feedback simulating actual operating conditions. The master handles may also include a variety of different actuators for delicate tissue manipulation or treatment further enhancing the surgeon's ability to mimic actual operating conditions.

Although the foregoing disclosure has been described in some detail by way of illustration and example, for purposes of clarity or understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims. 

1-20. (canceled)
 21. An electrosurgical instrument, comprising: a housing; an elongated shaft extending from the housing and defining a lumen therethrough; an end effector assembly disposed at a distal portion of the elongated shaft and configured to deliver electrosurgical energy to tissue; a key slot including a pair of openings defined through opposing sides of an outer surface of the elongated shaft; and a key member having a length greater than an outermost diameter of the elongated shaft, the key member received through the lumen via the key slot such that opposing ends of the key member extend outwardly from the opposing sides of the outer surface of the elongated shaft to prevent longitudinal movement of the elongated shaft.
 22. The electrosurgical instrument according to claim 21, wherein the housing defines an interior cavity defined between a distal wall and a proximal wall, each of the proximal and distal walls defining an annular clearance therethrough.
 23. The electrosurgical instrument according to claim 22, wherein a proximal portion of the elongated shaft extends through the annular clearance of each of the proximal and distal walls.
 24. The electrosurgical instrument according to claim 22, wherein the key member is rotatable within the cavity about a longitudinal axis defined by the elongated shaft upon rotation of the elongated shaft about the longitudinal axis.
 25. The electrosurgical instrument according to claim 22, further comprising a spindle disposed on a proximal portion of the elongated shaft and disposed within the annular clearance defined through the proximal wall, the spindle including a distal portion disposed within the cavity distal to the annular clearance defined by the proximal wall and a proximal portion disposed proximal to the annular clearance defined by the proximal wall.
 26. The electrosurgical instrument according to claim 25, wherein the key member is configured to engage at least one of the distal wall of the cavity or the distal portion of the spindle to prevent longitudinal movement of the elongated shaft.
 27. The electrosurgical instrument according to claim 25, further comprising a spring disposed on the elongated shaft and configured to compress against the proximal portion of the spindle.
 28. The electrosurgical instrument according to claim 25, wherein a diameter of the proximal and distal portions of the spindle is greater than a diameter of the annular clearance defined by the proximal wall.
 29. The electrosurgical instrument according to claim 21, wherein the key member is secured within the key slot via a friction fit between the key member and the elongated shaft.
 30. The electrosurgical instrument according to claim 21, wherein the key member is received through the lumen via the key slot along an axis defined transverse to a longitudinal axis defined by the elongated shaft.
 31. An electrosurgical instrument, comprising: a housing; an elongated shaft having a proximal portion disposed within the housing and defining a longitudinal axis; a pair of opposing jaw members disposed at a distal portion of the elongated shaft and configured to deliver electrosurgical energy to tissue; a key slot including a pair of openings defined through opposing sides of an outer surface of the proximal portion of the elongated shaft; and a key member having a length greater than an outermost diameter of the elongated shaft, the key member received through the elongated shaft via the key slot along an axis defined transverse to a the longitudinal axis such that opposing ends of the key member extend outwardly from the opposing sides of the outer surface, the opposing ends of the key member configured to contact a portion of the housing to prevent movement of the elongated shaft along the longitudinal axis.
 32. The electrosurgical instrument according to claim 31, wherein the opposing ends of the key member are configured to contact the portion of the housing to prevent distal movement of the elongated shaft along the longitudinal axis.
 33. The electrosurgical instrument according to claim 31, wherein the housing defines an interior cavity defined between a distal wall and a proximal wall, each of the proximal and distal walls defining an annular clearance therethrough.
 34. The electrosurgical instrument according to claim 33, wherein the proximal portion of the elongated shaft extends through the annular clearance of each of the proximal and distal walls.
 35. The electrosurgical instrument according to claim 33, wherein the key member is rotatable within the cavity about the longitudinal axis upon rotation of the elongated shaft about the longitudinal axis.
 36. The electrosurgical instrument according to claim 33, further comprising a spindle disposed on a proximal portion of the elongated shaft and disposed within the annular clearance defined through the proximal wall, the spindle including a distal portion disposed within the cavity distal to the annular clearance defined by the proximal wall and a proximal portion disposed proximal to the annular clearance defined by the proximal wall.
 37. The electrosurgical instrument according to claim 36, wherein the key member is configured to engage the distal wall of the cavity to prevent distal longitudinal movement of the elongated shaft and engage the distal portion of the spindle to prevent proximal longitudinal movement of the elongated shaft.
 38. A stopper assembly for preventing longitudinal movement of an elongated shaft of an electrosurgical instrument, comprising: a key slot including a pair of openings defined through opposing sides of an outer surface of an elongated shaft of an electrosurgical instrument; and a key member received through a lumen defined through the elongated shaft via the key slot such that opposing ends of the key member extend outwardly from the opposing sides of the outer surface of the elongated shaft, the opposing ends of the key member configured to engage a portion of the electrosurgical instrument to prevent longitudinal movement of the elongated shaft.
 39. The stopper assembly according to claim 38, wherein the key member is secured within the key slot via a friction fit between the key member and the elongated shaft.
 40. The stopper assembly according to claim 38, wherein the key member is received through the lumen via the key slot along an axis defined transverse to a longitudinal axis defined by the elongated shaft. 